Massive crayfish that didn't exist 25 years ago are capable of cloning themselves

[Fredrick]

Move over Rusty Crawfish here comes its bigger self reproducing cousin the Marbled Crawfish . Excluding the effects on native crawfish I wonder what kind of effect this crawfish would have on local fish populations. :-o




http://www.msn.com/en-us/news/technology/massive-crayfish-that-didnt-exist-25-years-ago-are-capable-of-cloning-themselves-%e2%80%94-and-its-terrifying-scientists/ar-BBIMqji?li=BBnb7Kz&ocid=UE07DHP

http://www.ibtimes.com/cloning-nature-all-marbled-crayfish-clones-one-individual-female-2650645

 

[PennypackFlyer]

I thought all crawfish looked the same to me.

 

[Hook_Jaw]

I've seen more of those big blue crayfish then I ever remember

 

[Mike]

I don't know what type of blue crayfish you are seeing or where, but there is a very blue morph of rusty crayfish. If there are rustles where you are seeing blue crayfish, I would suspect that there is a good chance that you are seeing the blue versions.

 

[Fredrick]

Here's a good pic of the blue rusty

http://www.fcal-wis.org/aquatic-invasive-species/rusty-crayfish-orconectes-rusticus/

 

[tomgamber]

NOTHING A LITTLE CAJUN SEASONING AND BUTTER CAN'T FIX.

 

[Hook_Jaw]

Yeah pretty much like the picture have seen some that are huge in penns creek

 

[salmonoid]

Fredrick wrote:
Move over Rusty Crawfish here comes its bigger self reproducing cousin the Marbled Crawfish . Excluding the effects on native crawfish I wonder what kind of effect this crawfish would have on local fish populations. :-o




http://www.msn.com/en-us/news/technology/massive-crayfish-that-didnt-exist-25-years-ago-are-capable-of-cloning-themselves-%e2%80%94-and-its-terrifying-scientists/ar-BBIMqji?li=BBnb7Kz&ocid=UE07DHP

http://www.ibtimes.com/cloning-nature-all-marbled-crayfish-clones-one-individual-female-2650645

I'm certainly not advocating for their release in PA streams, but they might enhance the size of other non-native fish (like browns), at the expense of the smaller native game and bait species. An almost constant on some of the smaller streams that I've fished that produce larger browns is an abundance of crayfish. They're not so noticeable during the day, but hit the water with a light at night and it looks like a zoo of crustaceans.

 

[ryanh]

I fished the Truckee river once in northern CA and I remember that it had the largest crayfish I had ever seen. They were monsters.

 

[ryansheehan]

salmonoid wrote:

Fredrick wrote:
Move over Rusty Crawfish here comes its bigger self reproducing cousin the Marbled Crawfish . Excluding the effects on native crawfish I wonder what kind of effect this crawfish would have on local fish populations. :-o




http://www.msn.com/en-us/news/technology/massive-crayfish-that-didnt-exist-25-years-ago-are-capable-of-cloning-themselves-%e2%80%94-and-its-terrifying-scientists/ar-BBIMqji?li=BBnb7Kz&ocid=UE07DHP

http://www.ibtimes.com/cloning-nature-all-marbled-crayfish-clones-one-individual-female-2650645

I'm certainly not advocating for their release in PA streams, but they might enhance the size of other non-native fish (like browns), at the expense of the smaller native game and bait species. An almost constant on some of the smaller streams that I've fished that produce larger browns is an abundance of crayfish. They're not so noticeable during the day, but hit the water with a light at night and it looks like a zoo of crustaceans.

I will advocate for releasing them in all PA trout streams, what could possibly go wrong?? ;-)

 

[Dave_W]

salmonoid wrote:
I'm certainly not advocating for their release in PA streams, but they might enhance the size of other non-native fish (like browns), at the expense of the smaller native game and bait species. An almost constant on some of the smaller streams that I've fished that produce larger browns is an abundance of crayfish. They're not so noticeable during the day, but hit the water with a light at night and it looks like a zoo of crustaceans.

I've long believed that crayfish are underrated as a big trout prey species, even on limestone streams. I find them in the stomachs of large stocked fish all the time, especially in the warmer months of the year. They also turn up a lot in my stream seine surveys. Many trout fishermen are largely unaware of the number of these critters in a typical trout stream because they don't see 'em... but salmonoid and guys who fish at night are spot-on about of how many there are. It's also a theory of mine that the bigger BTs that are common downstream where the water temps start to transition to warm water species are especially likely to specialize in munching crays at night.
Whaddaya think those big browns are after when they're out cruising at night? I'd bet on crayfish before mayfly spinners.

While we certainly don't need any more invasives, the importance of crayfish as bass food is much better known. The rusties have really taken over the lower Susky and some folks think that the massive crayfish biomass is leading to bigger and heavier SMBs these days. I suspect that rusties are also going a long way to feeding the younger flatheads too. Invasives eating invasives. :-o

 

[jifigz]

Mike wrote:
I don't know what type of blue crayfish you are seeing or where, but there is a very blue morph of rusty crayfish. If there are rustles where you are seeing blue crayfish, I would suspect that there is a good chance that you are seeing the blue versions.

The crayfish that I'm used to turn blue when they are molting. That is an easy way to tell which individuals are "soft" and the best bass bait before you grab them.

 

[jifigz]

And I agree. Lots of crayfish in many of our trout waters, especially the bigger streams. Little J, Kish, Penns are all loaded with them and I think the big trout feed on them much more than most realize.

The cloning crayfish thing is pretty wild though.

 

[lycoflyfisher]

While in college we were trying to crunch some data on factors that impacted trout growth rates. Our data size was definitely on the small side and we did not intend to look at this variable. However, with data from brook trout only streams (these were small headwater streams in the Kettle Creek Watershed) crayfish had a negative impact on brook trout growth rates. It was not a significant difference, but it was really close. Everyone understands how infertile many of the small forested freestoners are, so it would make sense that there is direct competition for food when crayfish are also present.

When concerning larger trout, there is no doubt that crayfish are an important part of their diet.

 

[JakesLeakyWaders]

I tie at least a dozen or two of these a year in all different sizes. A couple times I've caught big browns in holes I thought were empty. Even hooked up on some carp and a few big channel catfish while bass fishing a crayfish pattern. There is no doubt fish eat the hell out of crayfish. A super slow sinking pattern with an ocassional twitch is dinner.

 

[jifigz]

Nice looking craw pattern Jake. And yeah, crayfish certainly get eaten by just about any fish that can fit them in their mouth.

 

[PennKev]

jifigz wrote:
And I agree. Lots of crayfish in many of our trout waters, especially the bigger streams. Little J, Kish, Penns are all loaded with them and I think the big trout feed on them much more than most realize.

The cloning crayfish thing is pretty wild though.

An appropriate size and color Pat's Rubber Legs is a great crayfish imitation and works great on many of the larger central PA streams. Drift it deep and twitch it every once in a while. When the fish want it, they will crush it.